1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com> 4 * 2005-2007 Takahiro Hirofuchi 5 */ 6 7 #include <libudev.h> 8 9 #include <errno.h> 10 #include <stdio.h> 11 #include <string.h> 12 13 #include <getopt.h> 14 15 #include "usbip_common.h" 16 #include "utils.h" 17 #include "usbip.h" 18 #include "sysfs_utils.h" 19 20 static const char usbip_unbind_usage_string[] = 21 "usbip unbind <args>\n" 22 " -b, --busid=<busid> Unbind " USBIP_HOST_DRV_NAME ".ko from " 23 "device on <busid>\n"; 24 25 void usbip_unbind_usage(void) 26 { 27 printf("usage: %s", usbip_unbind_usage_string); 28 } 29 30 static int unbind_device(char *busid) 31 { 32 char bus_type[] = "usb"; 33 int rc, ret = -1; 34 35 char unbind_attr_name[] = "unbind"; 36 char unbind_attr_path[SYSFS_PATH_MAX]; 37 char rebind_attr_name[] = "rebind"; 38 char rebind_attr_path[SYSFS_PATH_MAX]; 39 40 struct udev *udev; 41 struct udev_device *dev; 42 const char *driver; 43 44 /* Create libudev context. */ 45 udev = udev_new(); 46 47 /* Check whether the device with this bus ID exists. */ 48 dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid); 49 if (!dev) { 50 err("device with the specified bus ID does not exist"); 51 goto err_close_udev; 52 } 53 54 /* Check whether the device is using usbip-host driver. */ 55 driver = udev_device_get_driver(dev); 56 if (!driver || strcmp(driver, "usbip-host")) { 57 err("device is not bound to usbip-host driver"); 58 goto err_close_udev; 59 } 60 61 /* Unbind device from driver. */ 62 snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s", 63 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME, 64 USBIP_HOST_DRV_NAME, unbind_attr_name); 65 66 rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid)); 67 if (rc < 0) { 68 err("error unbinding device %s from driver", busid); 69 goto err_close_udev; 70 } 71 72 /* Notify driver of unbind. */ 73 rc = modify_match_busid(busid, 0); 74 if (rc < 0) { 75 err("unable to unbind device on %s", busid); 76 goto err_close_udev; 77 } 78 79 /* Trigger new probing. */ 80 snprintf(rebind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s", 81 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME, 82 USBIP_HOST_DRV_NAME, rebind_attr_name); 83 84 rc = write_sysfs_attribute(rebind_attr_path, busid, strlen(busid)); 85 if (rc < 0) { 86 err("error rebinding"); 87 goto err_close_udev; 88 } 89 90 ret = 0; 91 info("unbind device on busid %s: complete", busid); 92 93 err_close_udev: 94 udev_device_unref(dev); 95 udev_unref(udev); 96 97 return ret; 98 } 99 100 int usbip_unbind(int argc, char *argv[]) 101 { 102 static const struct option opts[] = { 103 { "busid", required_argument, NULL, 'b' }, 104 { NULL, 0, NULL, 0 } 105 }; 106 107 int opt; 108 int ret = -1; 109 110 for (;;) { 111 opt = getopt_long(argc, argv, "b:", opts, NULL); 112 113 if (opt == -1) 114 break; 115 116 switch (opt) { 117 case 'b': 118 ret = unbind_device(optarg); 119 goto out; 120 default: 121 goto err_out; 122 } 123 } 124 125 err_out: 126 usbip_unbind_usage(); 127 out: 128 return ret; 129 } 130